20 research outputs found
Supersymmetry in quantum mechanics with point interactions
We investigate supersymmetry in one-dimensional quantum mechanics with point
interactions. We clarify a class of point interactions compatible with
supersymmetry and present N=2 supersymmetric models on a circle with two point
interactions as well as a superpotential. A hidden su(2) structure inherent in
the system plays a crucial role to construct the N=2 supercharges. Spontaneous
breaking of supersymmetry due to point interactions and an extension to higher
N-extended supersymmetry are also discussed.Comment: 12 pages, no figures. Some sections are improved and new references
are adde
Supersymmetry and discrete transformations on S^1 with point singularities
We investigate N-extended supersymmetry in one-dimensional quantum mechanics
on a circle with point singularities. For any integer n, N=2n supercharges are
explicitly constructed and a class of point singularities compatible with
supersymmetry is clarified. Key ingredients in our construction are n sets of
discrete transformations, each of which forms an su(2) algebra of spin 1/2. The
degeneracy of the spectrum and spontaneous supersymmetry breaking are briefly
discussed.Comment: 11 pages, 3 figure
Prevention of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis by Endoscopic Pancreatic Stenting after Insertion of Self-Expandable Metal Stent for Malignant Distal Biliary Stricture
The insertion of a self-expandable metal stent (SEMS) for nonpancreatic cancer is a factor predicting the risk of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP). We evaluated the efficacy of endo-scopic pancreatic stenting (EPS) to prevent PEP after SEMS insertion in patients with malignant distal biliary stricture and without main pancreatic duct (MPD) obstruction. We performed a single-center, retrospective, historically controlled investigation to assess the outcomes of 33 consecutive patients who underwent SEMS insertion. From March 2013 to June 2015, 13 patients did not undergo EPS (Non-EPS group). The other 20 patients underwent EPS (EPS group) between July 2015 and August 2018. The background data demonstrated no signiïŹcant differences. Except for one patient in the Non-EPS group, all patients underwent biliary sphinc-terotomy. The EPS groupâs PEP incidence was signiïŹcantly lower (n = 1, 5%) than that of the Non-EPS group (n = 4, 31%) (p = 0.04). The median serum amylase and lipase levels after the procedure were signiïŹcantly lower in the EPS group than in the Non-EPS group (amylase: 104 vs. 262 U/L; p < 0.01, lipase: 102 vs. 666 U/L; p = 0.01). The use of EPS decreased the incidence of PEP after SEMS insertion in individuals with malignant distal biliary stricture and without MPD obstruction
Should the provision of home help services be contained?: Validation of the new preventive care policy in Japan
<p>Abstract</p> <p>Background</p> <p>To maintain the sustainability of public long-term care insurance (LTCI) in Japan, a preventive care policy was introduced in 2006 that seeks to promote active improvement in functional status of elderly people who need only light care. This policy promotes the use of day care services to facilitate functional improvement, and contains the use of home help services that provide instrumental activity of daily living (IADL) support. However, the validity of this approach remains to be demonstrated.</p> <p>Methods</p> <p>Subjects comprised 241 people aged 65 years and over who had recently been certified as being eligible for the lightest eligibility level and had began using either home help or day care services between April 2007 and October 2008 in a suburban city of Tokyo. A retrospective cohort study was conducted ending October 2009 to assess changes in the LTCI eligibility level of these subjects. Cox's proportional hazards model was used to calculate the relative risk of declining in function to eligibility Level 4 among users of the respective services.</p> <p>Results</p> <p>Multivariate analysis adjusted for factors related to service use demonstrated that the risk of decline in functional status was lower for users of home help services than for users of day care services (HR = 0.55, 95% CI: 0.31-0.98). The same result was obtained when stratified by whether the subject lived with family or not. Furthermore, those who used two or more hours of home help services did not show an increase in risk of decline when compared with those who used less than two hours.</p> <p>Conclusions</p> <p>No evidence was obtained to support the effectiveness of the policy of promoting day care services and containing home help services for those requiring light care.</p
Achieving LDL cholesterol target levels <1.81 mmol/L may provide extra cardiovascular protection in patients at high risk: Exploratory analysis of the Standard Versus Intensive Statin Therapy for Patients with Hypercholesterolaemia and Diabetic Retinopathy study
Aims To assess the benefits of intensive statin therapy on reducing cardiovascular (CV) events in patients with type 2 diabetes complicated with hyperlipidaemia and retinopathy in a primary prevention setting in Japan. In the intension-to-treat population, intensive therapy [targeting LDL cholesterol = 2.59 to = 100 to = 2.59 to <3.10 mmol/L in patients with hypercholesterolaemia and diabetic retinopathy
Congenital atrial standstill associated with coinheritance of a novel SCN5A mutation and connexin 40 polymorphisms
The novel SCN5A mutation L212P was identified in the proband (age 11 years) and his father. The father was in normal sinus rhythm. The proband had no P waves on surface ECG, and his right atrium could not be captured by pacing. The recombinant L212P Na channel showed a large hyperpolarizing shift in both the voltage dependence of activation (WT: â48.1 ± 0.9 mV; L212P: â63.5 ± 1.5 mV; P < .001) and inactivation (WT: â86.6 ± 0.9 mV; L212P: â95.6 ± 0.8 mV; P < .001) and delayed recovery from inactivation. Further screenings for genetic variations that might mitigate L212P dysfunction revealed that the proband, but not his father, carries Cx40 polymorphisms inherited from his asymptomatic mother
Prevention of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis by Endoscopic Pancreatic Stenting after Insertion of Self-Expandable Metal Stent for Malignant Distal Biliary Stricture
Congenital atrial standstill associated with coinheritance of a novel SCN5A mutation and connexin 40 polymorphisms
Synthesis of Sulfides and Persulfides Is Not Impeded by Disruption of Three Canonical Enzymes in Sulfur Metabolism
Reactive sulfur species, or persulfides and polysulfides, such as cysteine hydropersulfide and glutathione persulfide, are endogenously produced in abundance in both prokaryotes and eukaryotes, including mammals. Various forms of reactive persulfides occur in both low-molecular-weight and protein-bound thiols. The chemical properties and great supply of these molecular species suggest a pivotal role for reactive persulfides/polysulfides in different cellular regulatory processes (e.g., energy metabolism and redox signaling). We demonstrated earlier that cysteinyl-tRNA synthetase (CARS) is a new cysteine persulfide synthase (CPERS) and is responsible for the in vivo production of most reactive persulfides (polysulfides). Some researchers continue to suggest that 3-mercaptopyruvate sulfurtransferase (3-MST), cystathionine ÎČ-synthase (CBS), and cystathionine Îł-lyase (CSE) may also produce hydrogen sulfide and persulfides that may be generated during the transfer of sulfur from 3-mercaptopyruvate to the cysteine residues of 3-MST or direct synthesis from cysteine by CBS/CSE, respectively. We thus used integrated sulfur metabolome analysis, which we recently developed, with 3-MST knockout (KO) mice and CBS/CSE/3-MST triple-KO mice, to elucidate the possible contribution of 3-MST, CBS, and CSE to the production of reactive persulfides in vivo. We therefore quantified various sulfide metabolites in organs derived from these mutant mice and their wild-type littermates via this sulfur metabolome, which clearly revealed no significant difference between mutant mice and wild-type mice in terms of reactive persulfide production. This result indicates that 3-MST, CBS, and CSE are not major sources of endogenous reactive persulfide production; rather, CARS/CPERS is the principal enzyme that is actually involved in and even primarily responsible for the biosynthesis of reactive persulfides and polysulfides in vivo in mammals